The disease appears when the disturbance of the ratio between the number of rods and cones in your eyes. Also, night blindness can develop in pathological decrease in the number of sticks, change their structure with the appearance of dysfunctionality.
Also, the reason night blindness is the lack or disruption of metabolic processes of the visual pigment — rhodopsin. It contains in the sticks.
Night blindness klassificeret into 3 types — congenital, essential, symptomatic. The most common — essential hemeralopia. It occurs due to malnutrition, deficiency of vitamins and minerals, especially the lack of vitamin A.
Also, this type of night blindness can be caused by anemia, liver disorders, poisoning by toxic poisons, exhaustion of the body.
Night blindness symptomatic — the result of certain eye diseases, including high myopia, glaucoma, disorders of the retina.
Congenital night blindness is due to hereditary diseases and genomic anomalies, such as usher syndrome, pigment retinitis.